Circular ducts used in ventilation systems are spiral ducting, seam-welded and butt-welded ducts. The most popular type of ducting is a spiral duct. Spiral duct is often referred to as "spiro" duct/tube because one of the most popular brands of tubeformers (spiral duct machines) are manufactured by Spiro International S.A.
Spiral ducting and fittings are produced in diameters range 80 mm to 1600 mm of galvanised steel, aluminium and stainless steel sheet. The standard length of a spiral tube - 3 metres. For easier delivery, we can manufacture shorter spiral ducting, e.g. 1-1.5 meter long sections to be transported on the pallets or in crated boxes. Check our Good Practices for Spiral Duct Installation, Transport and Storage.
Galvanised ducting is a standard type of ducting, though for more aggressive or special environments e.g. swimming pools or food industry buildings we can offer stainless steel spiral ducting with the addition of molybdenum. If You're looking for chemically resistant ductwork - see our chemically resistant plastic ducting.
The thickness of the sheet for typical elements depends on the diameter and equals to 0.5 - 1.5 mm. Spirally wound duct sizes above 250 mm diameter are additionally corrugated to increase their negative pressure resistance.
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Circular ducting are manufactured from galvanized (standard), stainless steel,
|Galvanised ducting - spiral ducts|
The available sheet thickness ranges from 0.5 to 0.8 mm. The
|Plain seam-welded ducts|
The available sheet thickness ranges from 0.5 to 0.9 mm. Butt
|Plain butt-welded ducts|
Stainless steel spiral ducts available in diameters from 80 to 1600mm from diameter 250mm they are provided with external ribs to increase their stiffness and resistance to negative pressure.
Stainless steel grades:
|Stainless steel round spiral ducts|
Round spiral ducts available in diameters from 80 to 1600mm from diameter 250mm they are provided with external corrugations to increase their stiffness and resistance to negative pressure. Although, as a standard, we sell air ducts made of galvanised steel sheet, we offer also ones made of copper, taking into consideration its antimicrobial benefits. Due to the fact that copper is known to suppress the growth of bacteria, fungi and molds, copper ductwork is a perfect solution for hospitals, schools, healthcare facilities like nursing homes and laboratories.
|Copper sheet round spiral ducts|
SPRP Round spiral perforated ducts are available in diameters from 80 to 630mm;
Perforated spiral ducts can be used in duct silencer production and for diffuser construction.
|Round spiral perforated ducts|
The WOOD-BOX are used for transportation of spiral round ducts.
High durability allows for stacking the boxes as well as to place
|Boxes for spiro ventilation ducts|
The racks are designed for storage and shipping of SPIRAL round ducts. They can accommodate ducts in the nominal diameter range of 80 mm to 315 mm. If the box capacity needs to be maximized, ducts of max. 3 different nominal diameters can be boxed by placing smaller tubes into larger ones. An empty rack can be collapsed and stacked to save space in warehouses and on transport vehicles.
|Storage racks for spiro ventilation ducts|